public class DevUse {
    public static void main (String[] args) {
        System.out.println(10 / 3);
        System.out.println(10.0 / 3);

        double d = 10 / 3; //3 -- > 3.0
                           //int --> double(隐式转换)
        System.out.println(d);
    }
}
